Field of the Invention
The solution according to one ore more embodiments of the invention generally relates to wireless communications networks, such as cellular networks. More particularly, the proposed solution relates to radio resources management for cellular networks, such as cellular networks based on LTE (“Long Term Evolution”)/LTE-Advanced, WiMAX (“Worldwide Interoperability for Microwave Access”) and any other OFDMA (“Orthogonal Frequency Division Multiple Access”) based technologies.
Overview of the Related Art
The cellular networks, conceived for allowing high-speed transmission of data streams between a fixed-location transceiver base station (e.g., eNodeB in LTE/LTE-Advanced technology) defining a respective network cell, and user equipments (e.g., user terminals, such as cellular phones) within the network cell, have experimented a significant growth in terms of performance.
However, due to the growing number of cellular network users, and to the growing demand for services requiring very high data traffic (such as internet, multimedia and real-time services), cellular networks could not satisfy all quality requirements.
A common issue affecting most of the cellular networks is radio resources allocation among the data streams (so that corresponding radio frequency data signals, or data signals, are allowed to propagate between the base station and the user equipments).
As known, the radio resources allocation may be different for transmissions taking place from the base station to the user equipment (downlink transmissions) and for transmissions taking place from the user terminal to the base station (uplink transmissions).
In the state of the art, solutions are known aimed at providing radio resources allocation in uplink transmissions.
U.S. Pat. No. 7,778,217 discloses an uplink scheduling system and method in a wireless broadband internet communication system comprising: calculating priorities of mobile stations taking into account headroom size indicating transmission power additionally available for each of the mobile stations; and determining a transmission format of a mobile station selected to be preferentially allocated a slot as a result of the priority calculation, taking into account headroom size reported by the selected mobile station and a margin determined depending on a variation in channel state between the selected mobile station and a base station.
US2010/0271963 discloses a base station in an OFDMA system which determines a modulation and coding scheme to use for a packet of a certain size to be transmitted by a mobile station. The base station schedules transmissions by mobile stations and transmits packets. The base station includes a processing unit which determines a number of time-frequency resources required to transmit the packet for a modulation and coding scheme, determines a SINR based on the number of time-frequency resources used and available power at the mobile station, determines a transmission rate as a ratio of the packet size transmitted to the number of time-frequency resources used, sets a rate to zero if the determined SINR is lower than a threshold SINR required for the modulation and coding scheme, and selects the modulation and coding scheme with a highest transmission rate. The base station includes a memory storing modulation and coding schemes.
WO2012177189 discloses a method and a device for scheduling uplink transmission in a cellular radio system for a number of user equipments transmitting data over an air-interface, wherein each user equipment is associated with an individual uplink load factor. A cost function is formed based on the load factor for each user equipment that is to be scheduled for uplink transmission, wherein the cost function is approximated by a quadratic function. The throughput of all scheduled user equipments is maximized using a convex optimization of the sum of the individual cost functions, and the grant for uplink transmission is scheduled in accordance with the optimized cost functions.